cat-file: disable object/refname ambiguity check for batch mode

diff --git a/sha1_name.c b/sha1_name.c
index 85b6e757411861b298cc6bee446f73ad0e430df8..c1957f35c182af9bf91658fa37602cf4071c7c37 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -435,12 +435,33 @@ static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned l
 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 {
        static const char *warn_msg = "refname '%.*s' is ambiguous.";
+       static const char *object_name_msg = N_(
+       "Git normally never creates a ref that ends with 40 hex characters\n"
+       "because it will be ignored when you just specify 40-hex. These refs\n"
+       "may be created by mistake. For example,\n"
+       "\n"
+       "  git checkout -b $br $(git rev-parse ...)\n"
+       "\n"
+       "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
+       "examine these refs and maybe delete them. Turn this message off by\n"
+       "running \"git config advice.object_name_warning false\"");
+       unsigned char tmp_sha1[20];
        char *real_ref = NULL;
        int refs_found = 0;
        int at, reflog_len;
 
-       if (len == 40 && !get_sha1_hex(str, sha1))
+       if (len == 40 && !get_sha1_hex(str, sha1)) {
+               if (warn_on_object_refname_ambiguity) {
+                       refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
+                       if (refs_found > 0 && warn_ambiguous_refs) {
+                               warning(warn_msg, len, str);
+                               if (advice_object_name_warning)
+                                       fprintf(stderr, "%s\n", _(object_name_msg));
+                       }
+                       free(real_ref);
+               }
                return 0;
+       }
 
        /* basic@{time or number or -number} format to query ref-log */
        reflog_len = at = 0;
@@ -481,7 +502,9 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
        if (!refs_found)
                return -1;
 
-       if (warn_ambiguous_refs && refs_found > 1)
+       if (warn_ambiguous_refs &&
+           (refs_found > 1 ||
+            !get_short_sha1(str, len, tmp_sha1, GET_SHA1_QUIETLY)))
                warning(warn_msg, len, str);
 
        if (reflog_len) {
@@ -860,8 +883,8 @@ static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
 }
 
 struct grab_nth_branch_switch_cbdata {
-       long cnt, alloc;
-       struct strbuf *buf;
+       int remaining;
+       struct strbuf buf;
 };
 
 static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
@@ -871,7 +894,6 @@ static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
        struct grab_nth_branch_switch_cbdata *cb = cb_data;
        const char *match = NULL, *target = NULL;
        size_t len;
-       int nth;
 
        if (!prefixcmp(message, "checkout: moving from ")) {
                match = message + strlen("checkout: moving from ");
@@ -880,11 +902,12 @@ static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
 
        if (!match || !target)
                return 0;
-
-       len = target - match;
-       nth = cb->cnt++ % cb->alloc;
-       strbuf_reset(&cb->buf[nth]);
-       strbuf_add(&cb->buf[nth], match, len);
+       if (--(cb->remaining) == 0) {
+               len = target - match;
+               strbuf_reset(&cb->buf);
+               strbuf_add(&cb->buf, match, len);
+               return 1; /* we are done */
+       }
        return 0;
 }
 
@@ -895,7 +918,7 @@ static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
 static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
 {
        long nth;
-       int i, retval;
+       int retval;
        struct grab_nth_branch_switch_cbdata cb;
        const char *brace;
        char *num_end;
@@ -905,34 +928,22 @@ static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
        brace = strchr(name, '}');
        if (!brace)
                return -1;
-       nth = strtol(name+3, &num_end, 10);
+       nth = strtol(name + 3, &num_end, 10);
        if (num_end != brace)
                return -1;
        if (nth <= 0)
                return -1;
-       cb.alloc = nth;
-       cb.buf = xmalloc(nth * sizeof(struct strbuf));
-       for (i = 0; i < nth; i++)
-               strbuf_init(&cb.buf[i], 20);
-       cb.cnt = 0;
+       cb.remaining = nth;
+       strbuf_init(&cb.buf, 20);
+
        retval = 0;
-       for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
-       if (cb.cnt < nth) {
-               cb.cnt = 0;
-               for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
+       if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
+               strbuf_reset(buf);
+               strbuf_add(buf, cb.buf.buf, cb.buf.len);
+               retval = brace - name + 1;
        }
-       if (cb.cnt < nth)
-               goto release_return;
-       i = cb.cnt % nth;
-       strbuf_reset(buf);
-       strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
-       retval = brace-name+1;
-
-release_return:
-       for (i = 0; i < nth; i++)
-               strbuf_release(&cb.buf[i]);
-       free(cb.buf);
 
+       strbuf_release(&cb.buf);
        return retval;
 }